Crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate, compositions and methods of use thereof

ABSTRACT

Provided herein is a crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate. Pharmaceutical compositions comprising the crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate are also disclosed.

This application claims priority to U.S. Provisional application No.62/562,302, filed Sep. 22, 2017, the entirety of which is incorporatedherein by reference.

FIELD

Provided herein is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.Pharmaceutical compositions comprising such solid and methods of use fortreating, preventing, and managing various disorders are also providedherein.

BACKGROUND

Many compounds can exist in different crystal forms, or polymorphs,which exhibit different physical, chemical, and spectroscopicproperties. For example, certain polymorphs of a compound may be morereadily soluble in particular solvents, may flow more readily, or maycompress more easily than others. See, e.g., P. DiMartino, et al., J.Thermal Anal., 48:447-458 (1997). In the case of drugs, certain solidforms may be more bioavailable than others, while others may be morestable under certain manufacturing, storage, and biological conditions.

Polymorphic forms of a compound are known in the pharmaceutical arts toaffect, for example, the solubility, stability, flowability,fractability, and compressibility of the compound, as well as the safetyand efficacy of drug products comprising it. See, e.g., Knapman, K.Modern Drug Discoveries, 2000, 53. Therefore, the discovery of newpolymorphs of a drug can provide a variety of advantages.

The identification and selection of a solid form of a pharmaceuticalcompound are complex, given that a change in solid form may affect avariety of physical and chemical properties, which may provide benefitsor drawbacks in processing, formulation, stability, bioavailability,storage, handling (e.g., shipping), among other important pharmaceuticalcharacteristics. Useful pharmaceutical solids include crystalline solidsand amorphous solids, depending on the product and its mode ofadministration. Amorphous solids are characterized by a lack oflong-range structural order, whereas crystalline solids arecharacterized by structural periodicity. The desired class ofpharmaceutical solid depends upon the specific application; amorphoussolids are sometimes selected on the basis of, e.g., an enhanceddissolution profile, while crystalline solids may be desirable forproperties such as, e.g., physical or chemical stability.

Pomalidomide has a chemical name of4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione. Pomalidomideis a compound that inhibits, for example, LPS induced monocyte TNFα,IL-1β, IL-12, IL-6, MIP-1, MCP-1, GM-CSF, G-CSF, and COX-2 production,and may be used in treating various disorders. See, e.g., U.S. Pat. Nos.5,635,517, 6,316,471, 6,476,052, 7,393,863, 7,629,360, 7,863,297,8,198,262, 8,673,939, 8,735,428, 8,759,375, 8,722,647, and 9,282,215.Pomalidomide has direct anti-myeloma tumoricidal and immunomodulatoryactivities, and inhibits stromal cell support for multiple myeloma tumorcell growth. Pomalidomide inhibits proliferation and induces apoptosisof hematopoietic tumor cells. Additionally, pomalidomide inhibits theproliferation of lenalidomide-resistant multiple myeloma cell lines andsynergizes with dexamethasone in both lenalidomide-sensitive andlenalidomide-resistant cell lines to induce tumor cell apoptosis.Pomalidomide enhances T cell- and natural killer (NK) cell-mediatedimmunity, and inhibits production of pro-inflammatory cytokines (e.g.,TNF-α and IL-6) by monocytes. Pomalidomide also inhibits angiogenesis byblocking the migration and adhesion of endothelial cells. A moleculartarget of pomalidomide is cereblon, a protein that forms a ubiquitin E3ligase complex with DNA damage-binding protein (DDBA), culin 4 (CUL4)and protein Roc1. Pomalidomide binding to cereblon induces thepolyubiquitination of two substrate proteins Ikaros (IKF1) and Aiolos(IKZF3). Pomalidomide is known to have CNS penetration. Due to itsdiversified pharmacological properties, pomalidomide is useful intreating, preventing, and/or managing various diseases or disorders.

Pomalidomide and methods of synthesizing pomalidomide are described,e.g., in U.S. Pat. Nos. 5,635,517, 6,335,349, 6,316,471, 6,476,052,7,041,680, 7,709,502, and 7,994,327. The chemical structure ofpomalidomide has been known since at least the 1960s, but little isknown regarding solid forms. An amorphous solid and one crystalline form(anhydrous) have been described in WO 2013/126326. A novel crystallineform of pomalidomide is described herein.

Pomalidomide is the active ingredient in POMALYST®, which in combinationwith dexamethasone was approved by the FDA in 2013 for the treatment ofpatients with multiple myeloma who have received at least two priortherapies including lenalidomide and a proteasome inhibitor and havedemonstrated a disease progression on or within 60 days of completion ofthe last therapy. The label for POMALYST® can be found athttp://www.pomalyst.com/?pi=yes&gclid=CMP4keDY-tMCFZOCfgods7oPsA.

New polymorphic forms of4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione can furtherthe development of formulations for the treatment of chronic illnesses,and may yield numerous formulation, manufacturing and therapeuticbenefits.

SUMMARY

Provided herein is a crystalline form of pomalidomide. Also providedherein are pharmaceutical compositions comprising a crystalline form ofpomalidomide. Further provided herein are methods of treating orpreventing a variety of disease and disorders, which compriseadministering to a patient a therapeutically effective amount of acrystalline form of pomalidomide. Also provided herein are methods oftreating multiple myeloma, optionally in combination with dexamethasone.

Also provided herein are methods of preparing, isolating, andcharacterizing crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrateprovided herein.

Also provided herein are pharmaceutical compositions containingcrystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dionehemihydrate provided herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 provides a representative X-ray powder diffraction (XRPD) patternof crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dionehemihydrate.

FIG. 2 provides a representative differential scanning calorimetry (DSC)thermogram of crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.

FIG. 3 provides a representative thermogravimetric analysis (TGA)thermogram of crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.

FIG. 4 provides a representative thermogravimetric analysis (TGA)thermogram of crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.

FIG. 5 provides a representative infrared (IR) spectrum of crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.

DEFINITIONS

As used herein, and unless otherwise specified, the compound referred toherein by the name pomalidomide or4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione, correspondsto a compound of Formula (I), depicted below.

Pomalidomide can be obtained via standard, synthetic methods (see e.g.,U.S. Pat. No. 5,635,517).

Unless otherwise specified, the term “crystalline” and related termsused herein, when used to describe a substance, component, product, orform, mean that the substance, component, product, or form issubstantially crystalline, for example, as determined by X-raydiffraction. (see, e.g., Remington's Pharmaceutical Sciences, 20^(th)ed., Lippincott Williams & Wilkins, Philadelphia Pa., 173 (2000); TheUnited States Pharmacopeia, 37^(th) ed., 503-509 (2014)).

As used herein, and unless otherwise specified, the terms “about” and“approximately,” when used in connection with doses, amounts, or weightpercents of ingredients of a composition or a dosage form, mean a dose,amount, or weight percent that is recognized by one of ordinary skill inthe art to provide a pharmacological effect equivalent to that obtainedfrom the specified dose, amount, or weight percent. In certainembodiments, the terms “about” and “approximately,” when used in thiscontext, contemplate a dose, amount, or weight percent within 30%,within 20%, within 15%, within 10%, or within 5%, of the specified dose,amount, or weight percent.

As used herein, and unless otherwise specified, the terms “about” and“approximately,” when used in connection with a numeric value or rangeof values which is provided to characterize a particular solid form,e.g., a specific temperature or temperature range, such as, for example,that describes a melting, dehydration, desolvation, or glass transitiontemperature; a mass change, such as, for example, a mass change as afunction of temperature or humidity; a solvent or water content, interms of, for example, mass or a percentage; or a peak position, suchas, for example, in analysis by, for example, IR or Raman spectroscopyor XRPD; indicate that the value or range of values may deviate to anextent deemed reasonable to one of ordinary skill in the art while stilldescribing the solid form. Techniques for characterizing crystal formsand amorphous forms include, but are not limited to, thermal gravimetricanalysis (TGA), differential scanning calorimetry (DSC), X-ray powderdiffractometry (XRPD), single-crystal X-ray diffractometry, vibrationalspectroscopy, e.g., infrared (IR) and Raman spectroscopy, solid-stateand solution nuclear magnetic resonance (NMR) spectroscopy, opticalmicroscopy, hot stage optical microscopy, scanning electron microscopy(SEM), electron crystallography and quantitative analysis, particle sizeanalysis (PSA), surface area analysis, solubility studies, anddissolution studies. In certain embodiments, the terms “about” and“approximately,” when used in this context, indicate that the numericvalue or range of values may vary within 30%, 20%, 15%, 10%, 9%, 8%, 7%,6%, 5%, 4%, 3%, 2%, 1.5%, 1%, 0.5%, or 0.25% of the recited value orrange of values. In the context of molar ratios, “about” and“approximately” indicate that the numeric value or range of values mayvary within 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1.5%, 1%,0.5%, or 0.25% of the recited value or range of values. It should beunderstood that the numerical values of the peaks of an X-ray powderdiffraction pattern may vary from one machine to another, or from onesample to another, and so the values quoted are not to be construed asabsolute, but with an allowable variability, such as ±0.2 degrees twotheta (° 20), or more. For example, in some embodiments, the value of anXRPD peak position may vary by up to ±0.2 degrees 2θ while stilldescribing the particular XRPD peak.

As used herein, and unless otherwise specified, a solid form that is“substantially physically pure” is substantially free from other solidforms. In certain embodiments, a crystal form that is substantiallyphysically pure contains less than about 50%, 45%, 40%, 35%, 30%, 25%,20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.4%, 0.3%,0.2%, 0.1%, 0.05%, or 0.01% of one or more other solid forms on a weightbasis. The detection of other solid forms can be accomplished by anymethod apparent to a person of ordinary skill in the art, including, butnot limited to, diffraction analysis, thermal analysis, elementalcombustion analysis and/or spectroscopic analysis.

As used herein, and unless otherwise specified, a solid form that is“substantially chemically pure” is substantially free from otherchemical compounds (i.e., chemical impurities). In certain embodiments,a solid form that is substantially chemically pure contains less thanabout 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%,4%, 3%, 2%, 1%, 0.5%, 0.4%, 0.3%, 0.2%, 0.1%, 0.05%, or 0.01% of one ormore other chemical compounds on a weight basis. The detection of otherchemical compounds can be accomplished by any method apparent to aperson of ordinary skill in the art, including, but not limited to,methods of chemical analysis, such as, e.g., mass spectrometry analysis,spectroscopic analysis, thermal analysis, elemental combustion analysisand/or chromatographic analysis.

As used herein, and unless otherwise indicated, a chemical compound,solid form, or composition that is “substantially free” of anotherchemical compound, solid form, or composition means that the compound,solid form, or composition contains, in certain embodiments, less thanabout 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%,4%, 3%, 2%, 1%, 0.5%, 0.4%, 0.3%, 0.2% 0.1%, 0.05%, or 0.01% by weightof the other compound, solid form, or composition.

Unless otherwise specified, the terms “solvate” and “solvated,” as usedherein, refer to a solid form of a substance which contains solvent. Theterms “hydrate” and “hydrated” refer to a solvate wherein the solvent iswater. The term “hemihydrate” refers to a hydrate containingapproximately one mole of water per two moles of compound.

As used herein, and unless otherwise specified, the terms “treat,”“treating” and “treatment” refer to the eradication or amelioration of adisease or disorder, or of one or more symptoms associated with thedisease or disorder. In certain embodiments, the terms refer tominimizing the spread or worsening of the disease or disorder resultingfrom the administration of one or more prophylactic or therapeuticagents to a subject with such a disease or disorder. In someembodiments, the terms refer to the administration of a compoundprovided herein, with or without other additional active agent, afterthe onset of symptoms of a particular disease.

Unless otherwise specified, the term “composition” as used herein isintended to encompass a product comprising the specified ingredient(s)(and in the specified amount(s), if indicated), as well as any productwhich results, directly or indirectly, from combination of the specifiedingredient(s) in the specified amount(s). By “pharmaceuticallyacceptable,” it is meant a diluent, excipient, or carrier in aformulation must be compatible with the other ingredient(s) of theformulation and not deleterious to the recipient thereof.

Unless otherwise specified, the term “subject” is defined herein toinclude animals, such as mammals, including, but not limited to,primates (e.g., humans), cows, sheep, goats, horses, dogs, cats,rabbits, rats, mice, and the like. In specific embodiments, the subjectis a human.

Unless otherwise specified, to the extent that there is a discrepancybetween a depicted chemical structure of a compound provided herein anda chemical name of a compound provided herein, the chemical structureshall control.

DETAILED DESCRIPTION

Crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dionehemihydrate can be prepared by the methods described herein, includingthe methods described in the Example below, or by techniques known inthe art, including heating, cooling, freeze drying, lyophilization,quench cooling the melt, rapid solvent evaporation, slow solventevaporation, solvent recrystallization, antisolvent addition, slurryrecrystallization, crystallization from the melt, desolvation,recrystallization in confined spaces such as, e.g., in nanopores orcapillaries, recrystallization on surfaces or templates such as, e.g.,on polymers, recrystallization in the presence of additives, such as,e.g., co-crystal counter-molecules, desolvation, dehydration, rapidcooling, slow cooling, exposure to solvent and/or water, drying,including, e.g., vacuum drying, vapor diffusion, sublimation, grinding(including, e.g., cryo-grinding, solvent-drop grinding or liquidassisted grinding), microwave-induced precipitation, sonication-inducedprecipitation, laser-induced precipitation and precipitation from asupercritical fluid. The particle size of the resulting solid forms,which can vary, e.g., from nanometer dimensions to millimeterdimensions, can be controlled, e.g., by varying crystallizationconditions, such as, e.g., the rate of crystallization and/or thecrystallization solvent system, or by particle-size reductiontechniques, e.g., grinding, milling, micronizing or sonication.

While not intending to be bound by any particular theory, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate ischaracterized by physical properties, e.g., stability, solubility anddissolution rate, appropriate for pharmaceutical and therapeutic dosageforms. Moreover, while not wishing to be bound by any particular theory,crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dionehemihydrate is characterized by physical properties (e.g., density,compressibility, hardness, morphology, cleavage, stickiness, solubility,water uptake, electrical properties, thermal behavior, solid-statereactivity, physical stability, and chemical stability) affectingparticular processes (e.g., yield, filtration, washing, drying, milling,mixing, tableting, flowability, dissolution, formulation, andlyophilization) which make certain solid forms suitable for themanufacture of a solid dosage form. Such properties can be determinedusing particular analytical chemical techniques, including solid-stateanalytical techniques (e.g., X-ray diffraction, microscopy, spectroscopyand thermal analysis), as described herein and known in the art.

Certain embodiments herein provide compositions comprising crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.Certain embodiments provide compositions of crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate incombination with other active ingredients. Certain embodiments providemethods of using these compositions in the treatment, prevention ormanagement of diseases and disorders including, but not limited to, thediseases and disorders provided herein.

Certain embodiments herein provide crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.In one embodiment provided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 12:1 THF/water mixture. In one embodimentprovided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 1:1 ethanol/water mixture. In one embodimentprovided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 2:4:2 ethanol/THF/water mixture. In oneembodiment provided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 5:1 ethanol/THF mixture. In one embodimentprovided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 1:1 1,4-dioxane/water mixture. In one embodimentprovided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 4:5 1,4-dioxane/water mixture. In one embodimentprovided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 3:1 1,4-dioxane/water mixture. In one embodimentprovided herein, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecan be obtained from a 6:1 THF/water mixture.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.

In certain embodiments, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratemay be characterized by X-ray powder diffraction analysis.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving an X-ray powder diffraction pattern comprising peaks at 12.0,17.2, and 25.6 degrees 2θ±0.2 degrees 2θ.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratewherein the X-ray powder diffraction pattern further comprises peaks at13.9, 16.7, and 24.3 degrees 2θ±0.2 degrees 2θ.

In certain embodiments, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate ischaracterized by XRPD peaks located at one, two, three, four, five, six,seven, eight, nine, ten, eleven or twelve of the following approximatepositions: 8.3, 11.6, 12.0, 12.7, 13.9, 16.4, 16.7, 17.2, 18.4, 19.2,19.9, 22.9, 24.3, 24.8, 25.6, 26.4, 27.9, 28.4, 28.9, 29.4, 30.8, 32.6,and 33.9 degrees 2θ. In certain embodiments, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate ischaracterized by an XRPD pattern which matches the pattern exhibited inFIG. 1. In certain embodiments, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate ischaracterized by an XRPD pattern having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 peaksmatching peaks in the representative XRPD pattern provided herein.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving an X-ray powder diffraction pattern corresponding to therepresentative X-ray powder diffraction patterns depicted in FIG. 1.

In certain embodiments, crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratemay be characterized by thermal analysis.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a differential scanning calorimetry thermogram comprising anendotherm with a maximum at about 317° C.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a differential scanning calorimetry thermogram corresponding tothe representative differential scanning calorimetry thermogramsdepicted in FIG. 2.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 3.2% of water by mass. In one embodiment, providedis a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 2.8% of water by mass. In one embodiment, providedis a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 2.9% of water by mass. In one embodiment, providedis a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 3.0% of water by mass. In one embodiment, providedis a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 3.3% of water by mass. In one embodiment, providedis a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 3.6% of water by mass. In one embodiment, providedis a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 3.7% of water by mass. In one embodiment, providedis a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving approximately 3.8% of water by mass.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a thermogravimetric analysis thermogram comprising a weight lossof between about 3.2% and about 4.3% when heated from about 30° C. toabout 225° C.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a thermogravimetric analysis thermogram comprising a weight lossof between about 2.8% and about 4.3% when heated from about 30° C. toabout 225° C.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a thermogravimetric analysis thermogram comprising a weight lossof about 3.2% when heated from about 30° C. to about 225° C.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a thermogravimetric analysis thermogram comprising a weight lossof about 4.3% when heated from about 30° C. to about 225° C.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a thermogravimetric analysis thermogram corresponding to therepresentative thermogravimetric analysis thermogram depicted in FIG. 3.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving a thermogravimetric analysis thermogram corresponding to therepresentative thermogravimetric analysis thermogram depicted in FIG. 4.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratehaving an infrared spectrum corresponding to the representative infraredspectrum depicted in FIG. 5.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratewhich is substantially physically pure.

In one embodiment, provided is a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratewhich is substantially chemically pure.

In one embodiment, provided is a pharmaceutical composition comprising acrystal form of4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.

Pharmaceutical Compositions

Pharmaceutical compositions and single unit dosage forms comprisingcrystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dionehemihydrate are provided herein. Also provided herein are methods forpreparing pharmaceutical compositions and single unit dosage formscomprising crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.For example, in certain embodiments, individual dosage forms comprisingcrystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dionehemihydrate provided herein or prepared using crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrateprovided herein may be suitable for oral, mucosal (including rectal,nasal, or vaginal), parenteral (including subcutaneous, intramuscular,bolus injection, intraarterial, or intravenous), sublingual,transdermal, buccal, or topical administration.

In certain embodiments, pharmaceutical compositions and dosage formsprovided herein comprise crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate.Certain embodiments herein provide pharmaceutical compositions anddosage forms comprising a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate,wherein the crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate issubstantially pure. Certain embodiments herein provide pharmaceuticalcompositions and dosage forms comprising a crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate asprovided herein, which is substantially free of other crystalline solidforms of 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dioneand/or amorphous solid forms of4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione.Pharmaceutical compositions and dosage forms provided herein typicallyalso comprise one or more pharmaceutically acceptable excipients,diluents or carriers.

Single unit dosage forms provided herein are suitable for oral orparenteral (e.g., subcutaneous, intravenous, bolus injection,intramuscular, or intraarterial) administration to a patient. Examplesof dosage forms include, but are not limited to: tablets; caplets;capsules, such as soft elastic gelatin capsules; powders and sterilesolids that can be reconstituted to provide liquid dosage forms suitablefor parenteral administration to a patient.

Capsules may contain a shell.

The composition, shape, and type of dosage forms provided herein willtypically vary depending on their use. A parenteral dosage form maycontain smaller amounts of one or more of the active ingredients itcomprises than an oral dosage form used to treat the same disease ordisorder. These and other ways in which specific dosage formsencompassed by this invention will vary from one another will be readilyapparent to those skilled in the art. See, e.g., Remington'sPharmaceutical Sciences, 18th ed., Mack Publishing, Easton Pa. (1990).

Typical pharmaceutical compositions and dosage forms comprise one ormore excipients. Suitable excipients are well known to those skilled inthe art of pharmacy, and non-limiting examples of suitable excipientsare provided herein. Whether a particular excipient is suitable forincorporation into a pharmaceutical composition or dosage form dependson a variety of factors well known in the art including, but not limitedto, the way in which the dosage form will be administered to a patient.For example, oral dosage forms such as tablets may contain excipientsnot suited for use in parenteral dosage forms. The suitability of aparticular excipient may also depend on the specific active ingredientsin the dosage form.

In one embodiment, suitable excipients include mannitol, pregelatinizedstarch, and sodium stearyl fumarate.

Capsule shells may contain gelatin, titanium dioxide, FD&C blue 2,yellow iron oxide, white ink, and black ink.

Capsule shells may contain gelatin, titanium dioxide, FD&C blue 2,yellow iron oxide, FD&C red 3, and white ink.

Capsule shells may contain gelatin, titanium dioxide, FD&C blue 2,yellow iron oxide, and white ink.

Capsule shells may contain gelatin, titanium dioxide, FD&C blue 1, FD&Cblue 2, and white ink.

Like the amounts and types of excipients, the amounts and specific typesof active ingredients in a dosage form may differ depending on factorssuch as, but not limited to, the route by which it is to be administeredto patients. However, typical dosage forms provided herein lie withinthe range of from about 0.1 mg to about 1,000 mg per day, given as asingle once-a-day dose in the morning or as divided doses throughout theday. More specifically, the daily dose may be administered twice, threetimes, or four times daily in equally divided doses. Specifically, adaily dose range may be from about 0.1 mg to about 500 mg per day, morespecifically, between about 0.1 mg and about 200 mg per day. A dailydose range may be 1 mg, 2 mg, 3 mg, 4 mg, or 5 mg. In managing thepatient, the therapy may be initiated at a lower dose, perhaps about 1mg to about 25 mg, and increased if necessary up to about 200 mg toabout 1,000 mg per day as either a single dose or divided doses,depending on the patient's global response.

Oral Dosage Forms

Pharmaceutical compositions provided herein that are suitable for oraladministration can be presented as discrete dosage forms, such as, butare not limited to, tablets (e.g., chewable tablets), caplets, capsules,and liquids (e.g., flavored syrups). Such dosage forms containpredetermined amounts of active ingredients, and may be prepared bymethods of pharmacy well known to those skilled in the art. Seegenerally Remington's Pharmaceutical Sciences, 18th ed., MackPublishing, Easton Pa. (1990).

Typical oral dosage forms provided herein are prepared by combining theactive ingredient(s) in an intimate admixture with at least oneexcipient according to conventional pharmaceutical compoundingtechniques. Excipients can take a wide variety of forms depending on theform of preparation desired for administration. For example, excipientssuitable for use in oral liquid or aerosol dosage forms include, but arenot limited to, water, glycols, oils, alcohols, flavoring agents,preservatives, and coloring agents. Examples of excipients suitable foruse in solid oral dosage forms (e.g., powders, tablets, capsules, andcaplets) include, but are not limited to, starches, sugars,micro-crystalline cellulose, diluents, granulating agents, lubricants,binders, and disintegrating agents.

If desired, tablets can be coated by standard aqueous or nonaqueoustechniques. Such dosage forms can be prepared by any of the methods ofpharmacy. In general, pharmaceutical compositions and dosage forms areprepared by uniformly and intimately admixing the active ingredientswith liquid carriers, finely divided solid carriers, or both, and thenshaping the product into the desired presentation if necessary.

For example, a tablet can be prepared by compression or molding.Compressed tablets can be prepared by compressing in a suitable machinethe active ingredients in a free-flowing form such as powder orgranules, optionally mixed with an excipient. Molded tablets can be madeby molding in a suitable machine a mixture of the powdered compoundmoistened with an inert liquid diluent.

Examples of excipients that can be used in oral dosage forms of theinvention include, but are not limited to, binders, fillers,disintegrants, and lubricants. Binders suitable for use inpharmaceutical compositions and dosage forms include, but are notlimited to, corn starch, potato starch, or other starches, gelatin,natural and synthetic gums such as acacia, sodium alginate, alginicacid, other alginates, powdered tragacanth, guar gum, cellulose and itsderivatives (e.g., ethyl cellulose, cellulose acetate, carboxymethylcellulose calcium, sodium carboxymethyl cellulose), polyvinylpyrrolidone, methyl cellulose, pre-gelatinized starch, hydroxypropylmethyl cellulose, (e.g., Nos. 2208, 2906, 2910), microcrystallinecellulose, and mixtures thereof.

Examples of fillers suitable for use in the pharmaceutical compositionsand dosage forms disclosed herein include, but are not limited to, talc,calcium carbonate (e.g., granules or powder), microcrystallinecellulose, powdered cellulose, dextrates, kaolin, mannitol, silicicacid, sorbitol, starch, pre-gelatinized starch, and mixtures thereof.The binder or filler in pharmaceutical compositions of the invention istypically present in from about 50 to about 99 weight percent of thepharmaceutical composition or dosage form.

Suitable forms of microcrystalline cellulose include, but are notlimited to, the materials sold as AVICEL-PH-101™, AVICEL-PH-103™, AVICELRC-581™, AVICEL-PH-105™ (available from FMC Corporation, AmericanViscose Division, Avicel Sales, Marcus Hook, Pa.), and mixtures thereof.A specific binder is a mixture of microcrystalline cellulose and sodiumcarboxymethyl cellulose sold as AVICEL RC-58™. Suitable anhydrous or lowmoisture excipients or additives include AVICEL-PH-103™ and Starch 1500LM™.

Disintegrants are used in the compositions provided herein to providetablets that disintegrate when exposed to an aqueous environment.Tablets that contain too much disintegrant may disintegrate in storage,while those that contain too little may not disintegrate at a desiredrate or under the desired conditions. Thus, a sufficient amount ofdisintegrant that is neither too much nor too little to detrimentallyalter the release of the active ingredients should be used to form solidoral dosage forms of the invention. The amount of disintegrant usedvaries based upon the type of formulation, and is readily discernible tothose of ordinary skill in the art. Typical pharmaceutical compositionscomprise from about 0.5 to about 15 weight percent of disintegrant,specifically from about 1 to about 5 weight percent of disintegrant.

Disintegrants that can be used in pharmaceutical compositions and dosageforms provided herein include, but are not limited to, agar-agar,alginic acid, calcium carbonate, microcrystalline cellulose,croscarmellose sodium, crospovidone, polacrilin potassium, sodium starchglycolate, potato or tapioca starch, pre-gelatinized starch, otherstarches, clays, other algins, other celluloses, gums, and mixturesthereof.

Lubricants that can be used in pharmaceutical compositions and dosageforms provided herein include, but are not limited to, calcium stearate,magnesium stearate, mineral oil, light mineral oil, glycerin, sorbitol,mannitol, polyethylene glycol, other glycols, stearic acid, sodiumlauryl sulfate, talc, hydrogenated vegetable oil (e.g., peanut oil,cottonseed oil, sunflower oil, sesame oil, olive oil, corn oil, andsoybean oil), zinc stearate, ethyl oleate, ethyl laureate, agar, andmixtures thereof. Additional lubricants include, for example, a syloidsilica gel (AEROSIL 200™, manufactured by W.R. Grace Co. of Baltimore,Md.), a coagulated aerosol of synthetic silica (marketed by Degussa Co.of Plano, Tex.), CAB-O-SIL™ (a pyrogenic silicon dioxide product sold byCabot Co. of Boston, Mass.), and mixtures thereof. If used at all,lubricants are typically used in an amount of less than about one weightpercent of the pharmaceutical compositions or dosage forms into whichthey are incorporated.

Parenteral Dosage Forms

Parenteral dosage forms can be administered to patients by variousroutes including, but not limited to, subcutaneous, intravenous(including bolus injection), intramuscular, and intraarterial injection.Because their administration typically bypasses patients' naturaldefenses against contaminants, parenteral dosage forms are preferablysterile or capable of being sterilized prior to administration to apatient. Examples of parenteral dosage forms include, but are notlimited to, solutions ready for injection, dry products ready to bedissolved or suspended in a pharmaceutically acceptable vehicle forinjection, suspensions ready for injection, and emulsions.

Suitable vehicles that can be used to provide parenteral dosage formsprovided herein are well known to those skilled in the art. Examplesinclude, but are not limited to: Water for Injection USP; aqueousvehicles such as, but not limited to, Sodium Chloride Injection,Ringer's Injection, Dextrose Injection, Dextrose and Sodium ChlorideInjection, and Lactated Ringer's Injection; water-miscible vehicles suchas, but not limited to, ethyl alcohol, polyethylene glycol, andpolypropylene glycol; and non-aqueous vehicles such as, but not limitedto, corn oil, cottonseed oil, peanut oil, sesame oil, ethyl oleate,isopropyl myristate, and benzyl benzoate.

Compounds that increase the solubility of one or more of the activeingredients disclosed herein can also be incorporated into theparenteral dosage forms provided herein.

EXAMPLES

Preparation of crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate:10 mg of pomalidomide Form A (anhydrate) was placed in a 50 mL roundbottom flask with 24 mL THF and 2 mL water. The flask was then placed ona rotary evaporator with the bath temperature at 80° C. All of thepomalidomide dissolved. An aspirator vacuum was then applied and theyellow crystalline solid was obtained within about two minutes. Thesolid was further air dried by exposure for 2 hours.

Karl-Fischer titration revealed the crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydratecontained 3.0% water.

XRPD data for the crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate isshown below in Table 1.

Scan Type: Normal Start Angle: 3 deg Stop Angle: 35 deg. Num Points:1601 Step Size: 0.02 deg. Datafile Res: 1600 Scan Rate: 0.001000 ScanMode: Step Wavelength: 1.540562 Å

Tube divergent 2.00 mmTube scatter 4.00 mmDetector scatter 0.50 mmDetector reflection 0.30 mm

TABLE 1 XRPD data for crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrate. Position Intensity Rel. Int.(Deg) (Dsp.) (cps) (%) 8.3 10.6104 132.10 6.84 11.6 7.6238 292.59 15.1412.0 7.3394 1210.88 62.66 12.7 6.9703 332.80 17.22 13.9 6.3490 1175.5760.83 16.4 5.4082 399.07 20.65 16.7 5.3167 810.58 41.95 17.2 5.15231661.93 86.00 18.4 4.8287 741.18 38.35 19.2 4.6215 171.60 8.88 19.94.4576 185.19 9.58 22.9 3.8721 333.43 17.25 24.3 3.6631 1353.18 70.0224.8 3.5919 555.83 28.76 25.6 3.4773 1932.47 100.00 26.4 3.3782 256.7913.29 27.9 3.1938 672.83 34.82 28.4 3.1403 729.08 37.73 28.9 3.0893316.05 16.35 29.4 3.0378 353.07 18.27 30.8 2.9039 167.90 8.69 32.62.7471 171.60 8.88 33.9 2.6411 327.40 16.94

Additional experiments to prepare crystalline4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione hemihydrateare listed below.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 1:1ethanol:water solution at 80° C. The pomalidomide dissolved completelyin the solution. The solution was taken to dryness on a rotaryevaporator and dried at 100° C. for 2 hours. The resulting solid wasfound to have 3.0% water by TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 2:4:2ethanol:THF:water solution at 95° C. The pomalidomide dissolvedcompletely in the solution. The solution was taken to dryness on arotary evaporator and further air dried. The resulting solid was foundto have 3.0% water by TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 5:1 95%ethanol:THF solution at 90° C. The pomalidomide dissolved completely inthe solution. The solution was taken to dryness on a rotary evaporatorand vacuum dried at rt for 1 hour. The resulting solid was found to have3.1% water by TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 1:11,4-dioxane:water solution at 75° C. The pomalidomide dissolvedcompletely in the solution. The solution was taken to dryness on arotary evaporator, triturated with water and air dried. The resultingsolid was found to have 3.7% water by TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 4:51,4-dioxane:water solution at 85° C. The pomalidomide dissolvedcompletely in the solution. The solution was taken to dryness on arotary evaporator, triturated with water and air dried. The resultingsolid was found to have 2.8% water by TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 4:11,4-dioxane:water solution at 85° C. The pomalidomide dissolvedcompletely in the solution. The solution was taken to dryness on arotary evaporator, triturated with water and air dried, then left opento air for 10 d. The resulting solid was found to have 3.8% water by TGAanalysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 12:1THF:water solution at 80° C. The pomalidomide dissolved completely inthe solution. The solution was taken to dryness on a rotary evaporatorand air dried for 3 h. The resulting solid was found to have 3.3% waterby TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 3:11,4-dioxane:water solution at 75° C. The pomalidomide dissolvedcompletely in the solution. The solution was taken to dryness on arotary evaporator, triturated with water and vacuum dried. The resultingsolid was found to have 3.8% water by TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 1:11,4-dioxane:water solution at 80° C. The pomalidomide dissolvedcompletely in the solution. The solution was taken to dryness on arotary evaporator, triturated with water and air dried, then vacuumdried, then heated at 100 C for 14 h. The resulting solid was found tohave 3.6% water by TGA analysis.

ca. 50 mg pomalidomide Form A (anhydrate) was dissolved in a 6:1THF:water solution at 50° C. The pomalidomide dissolved completely inthe solution. The solution was taken to dryness on a rotary evaporatorand air dried. The resulting solid was found to have 2.9% water by TGAanalysis.

Additional Experiments that Did not Result in Crystalline4-Amino-2-(2,6-Dioxopiperidine-3-Yl)Isoindoline-1,3-Dione Hemihydrate

The following unsuccessful experiments were performed by mixing in aflask Form A of4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dione with solventsuntil dissolution, then the flask was placed on a rotoevapator (fastrotation; vacuum by water aspirator) at various bath temperatures untildryness or until apparent dryness.

Certain experiments produced an oil, which were then triturated asfollows: pure HPLC grade water was added to flask containing the oil,and the flask was stirred. If a solid was formed, it was further dried.

TABLE 2 Conditions that did not result in a crystalline hemihydrate of4-amino-2-(2,6- dioxopiperidine-3-yl)isoindoline-1,3-dione. Ratio ofsolvent/co- Temperature Solvent Co-solvent solvent (° C.) Notes1,4-dioxane N/A 60 THF Water 10:1  60 Triturated vacuum dried THF Water1:1 80 Ethanol Water 1:1 80 100° C. for 12 hours after initial dryingEthanol Water 1:1 80 Dried further for 20 min at 100° C., then 30 min at150° C. THF Water 1:1 80 1,4-dioxane Water 1:1 80 THF Water 24:5  80 THFWater 23:5  80 1,4-dioxane Water 1:1 80 Triturated, dried at 150° C. for1 h THF Water 95:5  65 Ethanol Water 95:5  90 Ethanol Water 98:2  90 THFWater 9:1 85 Ethanol THF/Water 2:1:2 60 Ethanol THF/Water 2:1:2 95Ethanol THF/Water 1:6:1 95 Ethanol THF/Water 6:4:1 95 Ethanol THF/Water1:2:1 95 1,4-dioxane Water 1:1 95 Triturated 1,4-dioxane Water 1:1 95Triturated, air tried, 45 m in vacuo Ethanol THF/Water 3:5:3 80 Airdried 3 h Ethanol THF/Water 3:5:3 80 Acetone i-PrOH/Water 1:1:1 90Acetone i-PrOH/Water 1:1:1 95 Material was moist Acetone i-PrOH/Water1:1:1 95 Air dried 18 h Acetone i-PrOH/Water 1:1:1 95 Air current dried3 h Acetone i-PrOH/Water 1:1:1 95 Air current dried 1 h Acetonei-PrOH/Water 1:1:1 85 1,4-dioxane Water 1:1 85 Material was moist THFWater 1:1 80 Air dried THF Water 1:1 80 Dried in vacuo for 2 h at 200°C. 1,4-dioxane Water 1:1 90 Triturated, dried in vacuo 16 h THF Water4:1 95 THF Water 4:1 80 THF Water 4:1 65 1,4-dioxane Water 1:1 951,4-dioxane Water 4:1 80 Oil, triturated, air dried 4 h 1,4-dioxaneWater 3:1 85 Air dried 3 h 1,4-dioxane Water 3:1 85 Dried overnight atroom temperature 1,4-dioxane Water 3:1 85 Triturated, dried THF Water4:1 80 Air dried 1 h THF Water 12:1  70 Air dried THF Water 6:1 80 Airdried MeCN Water 2:1 80 Material was moist MeCN Water 2:1 80 Driedovernight MeCN Water 2:1 90 Air dried 1,4-dioxane Ethanol/THF/Water1:1:1:2 85 Air dried 1,4-dioxane THF/Water 6:6:1 50 Material was moist1,4-dioxane THF/Water 6:6:1 50 Dried at 90° C. in vacuo 1,4-dioxaneTHF/Water 6:6:1 50 Air dried Acetone THF/Water 10:3:3 90 Air dried THFWater 25:1  60 Air dried THF Water 25:1  60 THF Water 20:1  70 THF Water4:1 80 Air dry THF Water 10:1  65 Air dry THF Water 10:1  75 AcetoneTHF/Water 10:1:1 60 Air dry 1,4-dioxane Water 3:1 85 Triturated1,4-dioxane Water 12:1  60 Triturated

Characterization Methodology

Samples generated as described in the solid form screen were typicallyanalyzed by X-Ray Powder Diffraction (XRPD). XRPD was conducted on aScintag X2 X-ray powder diffractometer using Cu Kα radiation at 1.54 Å.In general, positions of XRPD peaks are expected to individually vary ona measurement-by-measurement basis by about ±0.2° 2θ. In general, asunderstood in the art, two XRPD patterns match one another if thecharacteristic peaks of the first pattern are located at approximatelythe same positions as the characteristic peaks of the second pattern. Asunderstood in the art, determining whether two XRPD patterns match orwhether individual peaks in two XRPD patterns match may requireconsideration of individual variables and parameters such as, but notlimited to, preferred orientation, phase impurities, degree ofcrystallinity, particle size, variation in diffractometer instrumentsetup, variation in XRPD data collection parameters, and/or variation inXRPD data processing, among others. The determination of whether twopatterns match may be performed by eye and/or by computer analysis. Anexample of an XRPD pattern collected and analyzed using these methodsand parameters is provided herein, e.g., as FIG. 1.

Differential Scanning calorimetry (DSC) analyses were performed on a TAInstruments Q100™. About 5 mg of sample was placed into a tared DSCclosed aluminum pan and the weight of the sample was accuratelyrecorded. An example of a DSC thermogram collected and analyzed usingthese methods and parameters is provided herein, e.g., as FIG. 2.

Thermal Gravimetric Analyses (TGA) were performed on a TA InstrumentsQ50™. About 10 mg of sample was placed on an open aluminium pan,accurately weighed and loaded into the TGA furnace. An example of a TGAthermogram collected and analyzed using these methods and parameters isprovided herein, e.g., as FIG. 3.

An example of a TGA thermogram collected and analyzed using thesemethods and parameters is provided herein, e.g., as FIG. 4.

Water determination by the Karl Fischer method was performed using aMetrohm 831 KF Coulometer. The sample was dissolved in anhydrous acetoneand injected into the titrator.

Infrared spectroscopy was performed using a ThermoNicolet Nexus 670spectormeter. A sample of ca. 1 mg of the hemihydrate in ca. 100 mg KBr.The mixture was then pressed into a pellet, which was used for the IRstudy. An example of an IR spectrum collected and analyzed using thesemethods and parameters is provided herein, e.g., as FIG. 5.

The embodiments described above are intended to be merely exemplary, andthose skilled in the art will recognize, or will be able to ascertainusing no more than routine experimentation, numerous equivalents ofspecific compounds, materials, and procedures. All such equivalents areconsidered to be within the scope of the disclosure and are encompassedby the appended claims.

Citation or identification of any reference in this application is notan admission that such reference is available as prior art. The fullscope of the disclosure is better understood with reference to theappended claims.

1. Crystalline 4-amino-2-(2,6-dioxopiperidine-3-yl)isoindoline-1,3-dionehemihydrate.
 2. The hemihydrate of claim 1, having an X-ray powderdiffraction pattern comprising peaks at 12.0, 17.2, and 25.6 degrees2θ±0.2 degrees 2θ.
 3. The hemihydrate of claim 2, wherein the X-raypowder diffraction pattern further comprises peaks at 13.9, 16.7, and24.3 degrees 2θ±0.2 degrees 2θ.
 4. The hemihydrate of claim 1, having anX-ray powder diffraction pattern corresponding to the representativeX-ray powder diffraction pattern depicted in FIG.
 1. 5. The hemihydrateof claim 1, having a differential scanning calorimetry thermogramcomprising an endotherm with a maximum at about 317° C.
 6. Thehemihydrate of claim 1, having a differential scanning calorimetrythermogram corresponding to the representative differential scanningcalorimetry thermograms depicted in FIG.
 2. 7. The hemihydrate of claim1, having about 3.2% of water by mass.
 8. The hemihydrate of claim 1,having a thermogravimetric analysis thermogram comprising a weight lossof between about 2.8% and about 4.3% when heated from about 30° C. toabout 225° C.
 9. The hemihydrate of claim 1, having a thermogravimetricanalysis thermogram corresponding to the representativethermogravimetric analysis thermogram depicted in FIG.
 3. 10. Thehemihydrate of claim 1, having a thermogravimetric analysis thermogramcorresponding to the representative thermogravimetric analysisthermogram depicted in FIG.
 4. 11. The hemihydrate of claim 1, having aninfrared spectrum corresponding to the representative infrared spectrumdepicted in FIG.
 5. 12. The hemihydrate of claim 1, which issubstantially physically pure.
 13. The hemihydrate of claim 1, which issubstantially chemically pure.
 14. A pharmaceutical compositioncomprising the hemihydrate of claim 1.